Orion

First entry on my blog and this time I will be writing about the constellation Orion, I figured I'll talk about the constellations first because that is one way people map the night sky and also because I’m a big fan of deep sky objects compared to our solar system. Orion can be seen all over the world on the celestial equator. The name Orion comes from a hunter in Greek mythology, which states that Orion is fighting Taurus the alongside his two dogs (two other constellations) Canis major and Canis minor. The three bright stars in the middle lined up is the belt of the hunter and the four outer stars make up the shoulders and legs. The fuzzy cloud in between the belt and legs is the Orion Nebula which is said to be the hunter’s sword.

Orion is a great guider to other stars and constellations. Lined up with the belt going right is Aldebaran. Going left lined up with the belt is Sirius. If you line up the two shoulders and go left you will find Procyon. If you line up the right leg of the hunter to his left shoulder you will reach Castor and Pollux.

The Major Stars in Orion:



• Betelguese – (alpha orionis) the right shoulder, if orion was facing Earth. Betelguse M-type red supergiant, 19 solar masses (sun = 1 solar mass), also the second brightest star in Orion. This a semiregular variable star and will explode in a super nova soon (soon as in astronomical timescale). It will be bright enough to be visible during the day when it explodes. It is the ninth brightest star of the nightsky. Its magnitude varies between 0.2 and 1.2. This star is also the upper right vertex of the winter triangle. This star is one of the largest stars known; if the center of Betelguese was the center of our solar system, the surface would extend to Jupiter. Betelguese is 643 ly (light years) away.

• Rigel – (beta orionis) is the left foot of orion and is a B-type blue supergiant, 17 solar masses, that is the sixth brightest star in the night sky. Since Rigel is fusing heavy elements in its core, it will explode in a supernova soon and later turning into a white dwarf. The Magnitude of Rigel is 0.18 but is usually brighter than Betelguese. Rigel is the most luminous star in this portion of the Milky Way. Rigel is 800 ly away.

• Bellatrix –(gamma orionis) is the left shoulder of orion. Known as the Gamma Orionis and Amazon Star. Bellatrix is the twenty-second brightest star in the night sky. This B-type blue giant get most of its luminousity from its heat rather than radius. Bellatrix is 9 solar masses and has a magnitude of 1.59 - 1.64. Bellatrix is 240 ly away.

• Mintaka – (delta orionis) is the faintest of the three stars and the westernmost star in Orion’s belt. This star is a B-type supergiant and is part of a multi-star system along with a huge O-type white star. From our view the binary system’s stars eclipse one another making the brightness change. Mintaka has an absolute magnitude of -4.99 and is 20 solar masses. Both stars in this system are 90,000 times more luminous than the sun and orbit each other every 5.73 days. Mintaka is 900 ly away.

• Alnilam – (Epsilon Orionis) is a B-type blue supergiant. Even though it is twice as far away as the other two stars in Orion’s belt, it is just as luminous. Because of its massive size, Alnilam is losing mass very quickly and said to be only four million years old. This star is the thirtieth brightest star in the night sky and the fourth brightest in Orion. Alnilam is 40 solar masses big and 1300 ly away.

• Alnitak – (zeta orionis) is the easternmost star in orion’s belt. Alnitak is a triple star system but the primary star is the brightest class O star in the night sky being a very hot blue supergiant. Alnitak’s magnitude is -5.25 and is 28 solar masses big. Alnitak B is a fourth magnitude B-type star that orbits the primary star every 1500 years. The triple star system is neighbored by IC 434 a bright emission nebula. Alnitak is 800 ly away.

• Saiph – (Kappa Orionis) is the right foot of Orion. It is almost the same distance and size as Rigel but fainter because of a 26,000 C (46,000 F) surface temperature that it most of its light is emitted in the UV spectrum. Siaph is 17 solar masses big and has a magnitude of -4.66. Saiph is 700 ly away.

• Hatsya – (lota Orionis) is the tip of the sword of Orion. It is part of a quadruple star system which emits large amounts of x-rays. Hatsya has a magnitude of 2.77 and is 15 solar masses. Katsya is 1300 ly away.

• Meissa – (lamda Orionis) is the head of Orion. It is an O giant star that is part of a star cluster call Collinder 69. It is a binary system with a hot blue-white dwarf star. Its magnitude is 3.39 and is about 1100 ly away.


Orion will be seen in the night sky for another 1to 2 million years making it one of the longest observed constellation almost parallel time as the rise of humans on earth.

What other cultures think of Orion:

Hungarian – great hunter and warrior named Nimrod the mythological father of Hungarians.
Scandinavia – the scythe of Vainamoinen (a Finnish god in folklore) and Frigs distaff.
India – Mriga the Deer as said by Rig Veda.
China – called Shen (three) after the three stars in Orion’s belt.
Native Americans – called it Hapj in northern Mexico and the Aztecs called the belts, Fire Drill, which starts a new fire ceremony.
Australian – Julpan a canoe.

The Future:
Orion is seen in the equator and all over the world because of the tilt in earth’s axis, the wobble effects on its rotation is perfect timing for our millennia to view Orion. By 1400 CE Orion will not be visible in England because of the tilt of the earth wobbling back in place. Even though Orion will be recognized long after other constellations, it will one day slowly pull apart from each other disfiguring the shape. But by then most of the stars will be gone via supernovae such as Betelgeuse that probably only has a few thousand years left of its life.